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The magnetic properties of cobalt metal nanowires grown by electrodeposition in porous membranes depend largely on the synthesis conditions. Here, we focus on the role of electrolyte additives on the magnetic anisotropy of the electrodeposited nanowires. Through magnetometry and internal field nuclear magnetic resonance (IF NMR) studies, we compared both the magnetic and crystalline structures of 50 and 200 nm diameter Co nanowires synthesized in the presence or absence of organic additives. The spectral characteristics of IF NMR were compared structurally to X-ray diffraction patterns, and the anisotropy of the NMR enhancement factor in ferromagnetic multidomain structures to magnetometry results. While the magnetic behavior of the 50 nm nanowires was dominated, as expected, by shape anisotropy with magnetic domains oriented on axis, the analysis of the 200 nm proved to be more complex. 59Co IF NMR revealed that the determining difference between the samples electrodeposited in the presence or in absence of organic additives was not the dominant crystalline system (fcc or hcp) but the coherent domain sizes and boundaries. In the presence of organic additives, the cobalt crystal domains are smaller and with defective grain boundaries, as revealed by resonances below 210 MHz. This prevented the development in the Co hcp part of the sample of the strong magnetocrystalline anisotropy that was observed in the absence of organic additives. In the presence of organic additives, even in nanowires as wide as 200 nm, the magnetic behavior remained determined by the shape anisotropy with a positive effective magnetic anisotropy and strong anisotropy of the NMR enhancement factor.

Here we discuss barriers to reproducibility in regard to microscopes and related hardware, along with best practices for sharing novel designs created using computer-aided design (CAD). We hope to start a fruitful community discussion on how instrument development, especially in microscopy, can become more open and reproducible, ultimately leading to better, more trustworthy science.

Modern tools for biological research, especially microscopy, have rapidly advanced in recent years, which has led to the generation of increasingly large amounts of data on a regular basis. The result is that scientists desperately need state-of-the-art technical infrastructure for raw data storage, transfer, and processing. These scientists currently rely on outdated ways to move and store data, costing valuable time and risking loss of valuable data. While the community is aware of modern approaches to data management and high-level principles (including FAIR), highly-trained and highly-paid scientists are forced to spend time dealing with technical problems, which can ultimately costs more than providing storage and a fast network on campus. Here we provide concise arguments for better infrastructure, blueprints of possible solutions, and advice in navigating the political process of solving this issue. We suggest, as a broad solution, separate NIH-managed fund for supporting universities and institutes in deployment of data storage and long-term data sharing for all funded projects. This position statement is open for more contributors from imaging, life sciences, and other disciplines. Please contact us with your experience and perspective.

Experiments with biological samples require precise control of environmental conditions. In our work we use zebrafish (Danio rerio) to understand the neurobiology of sleep, which requires precise control of temperature and lighting. Like many labs, lighting and temperature in the animal facility are centrally controlled in the building. During behavioral experiments and microscopy sessions, we use custom-built heating systems and perform occasional manual checks of conditions. However, without a system to precisely record conditions, gradual changes in temperature can go unnoticed for a long time, and temporary failures may be missed entirely. Here we present the design and characterization of affordable open-source tools to record temperature and light conditions during animal experiments using an Arduino microcontroller or a Raspberry Pi compact computer. The waterproof temperature sensor has high stability over 50 days of recording and is precise to 0.1°C. The Arduino device can be used through a common serial port interface for which we present code in Python and MATLAB. The Raspberry Pi version can be accessed through a web interface, for which we provide an installation guide. We use the device to record and review temperature and lighting conditions in two zebrafish animal facilities. We use our platform to add a water heating system to maintain temperature at 28°C during in vivo light-sheet imaging of larval zebrafish. We show that a change in temperature from 28°C to 32°C affects resting heart rate of the animal, highlighting the importance of maintaining and recording conditions. The protocols presented here do not require advanced engineering, fabrication, or software skills, and provide an approach to accurately record and report experimental conditions.

The study has revealed the regularities of the effect produced by increasing the content of scale of steel 12Cr18Ni10Ti in the charge from 5 to 75 mass % on the contents of the products of carbon thermal reduction of oxide waste of corrosion-resistant steels. The concentration of Ni is increased from 0.8 to 7.0 mass % when the Cr content ranges from 15.9 to 17.1 mass %. The concentration of Cr in the extraction products within the range of 16.1–17.1 mass% is provided with the content of scale of 95Cr18 steel in the charge in the range from 5 to 55 mass %. It has been found that metallization products mainly consist of a solid solution of alloying elements in α-Fe. Fe3O4, Fe3C, and Fe2C were also identified. The microstructure of the extraction products is spongy and disordered. The particles are sintered, with varying Cr and Ni contents in the ranges of 7.47 to 18.03 mass % and 2.97–10.40 mass %, respectively. The study has helped achieve environmentally safe conditions for solid-phase extraction of chrome and nickel containing industrial wastes from the production of corrosion-resistant steels with the return of the alloyed product to the welding industry, Определены закономерности влияния параметров шихты на содержание Cr и Ni в продуктах восстановления. Достигнуты пределы содержания соответствующих элементов: 15,1–17,1 % мас. и 0,2–7,0 % мас. Установлено, что продукты металлизации в основном состояли из твердого раствора легирующих элементов в α-Fe. Также выявлены оксид Fe3O4 и карбиды – Fe3C, Fe2C. Микроструктура губчатая разупрядоченная. Микрочастицы спеченные, с различным содержанием Cr и Ni, Визначено закономірності впливу параметрів шихти на вміст Cr та Ni в продуктах відновлення. Досягнуто межі вмісту відповідних елементів: 15,1–17,1 % мас. та 0,2–7,0 % мас. Встановлено, що продукти металізації в основному складалися з твердого розчину легуючих елементів в α-Fe. Також виявлено оксид Fe3O4 і карбіди – Fe3C, Fe2C. Мікроструктура губчаста розупорядкована. Мікрочастки спечені, з різним вмістом Cr та Ni

"Die Autoren analysieren offizielle Statistiken der Streikbewegung in Rußland während der Jahre 1895 bis 1908 mit Methoden der Chaos-Theorie und entwickeln ein Modell zur Erklärung nicht-linearer Prozesse. Der Verlauf und die Häufigkeit der Streiks werden als Selbstorganisation der Industriearbeiter interpretiert, was der herkömmlichen Meinung nach dem Dominieren äußerer Faktoren widerspricht." (Autorenreferat), "Social conflicts often contain unpredictable peaks of activities and relatively long periods of non-stable behaviour. How could we explain such a non-linear, chaotic behaviour? What is more substantial - internal factors of these effects or external causes? Sometimes historians take into account only external factors as the main causes of the historical phenomena, though they possibly play the 'trigger' role in the processes of the 'social explosives'. Such questions can be asked in the investigation of the strike movement in Russia in the end of 19th and the beginning of the 20th century. One of possible ways to answer these questions is to apply the theory of non-linear systems with dynamically stochastic behaviour (or 'chaos'), developed in the last decades. We used official statistics of industrial strikes in the Russian Empire during the years 1895-1908. Our research demonstrates the possible appearance of 'chaos' (in mathematical sense) in the system behaviour and the existence of a rather long unstable period. To describe the development of strike movement we built the quantitative model. The system of the four non-linear ordinary differential equations was constructed after using advanced mathematical procedures to analyse the time-series. This model had a good predictor feature and for defined values of the coefficients demonstrated a chaotic behaviour. The research reveals the great role of the mechanism of information transfer and the significance of internal factors in the strike movement." (author's abstract)

The paper presents results of computer experiments performed for research to enhance operational parameters of multicavity magnetrons through using the metal-thin-wire (MTW) and the metal-split-ring (MSR) metamaterial structures as a cold (non-thermionic) cathode. It is demonstrated by particle-in-cell (PIC) simulations of a generic 10-vane non-relativistic ultra-high frequency (UHF) magnetron that the output microwave power and the start-up time of this magnetron are improved by replacing either a solid or a transparent cathode by a bulk MTW metamaterial structure formed by an array of individual wires directed parallel to the axis of the magnetron (rodded cathode)., See also ADM002371. 2013 IEEE Pulsed Power Conference, Digest of Technical Papers 1976-2013, and Abstracts of the 2013 IEEE International Conference on Plasma Science. IEEE International Pulsed Power Conference (19th). Held in San Francisco, CA on 16-21 June 2013., The original document contains color images.

The paper presents results of computer experiments performed for research to enhance operational parameters of multi-cavity magnetrons through using the metal-thin-wire (MTW) and the metal-split-ring (MSR) metamaterial structures as a cold (non-thermionic) cathode. It is demonstrated by particle-in-cell (PIC) simulations of a generic 10-vane non-relativistic ultra-high frequency (UHF) magnetron that the output microwave power and the start-up time of this magnetron are improved by replacing either a solid or a transparent cathode by a bulk MTW metamaterial structure formed by an array of individual wires directed parallel to the axis of the magnetron (rodded cathode)., The original document contains color images. Presented at the 18th IEEE International Pulsed Power Conference on 19 Jun 2011.

Using shipborne and satellite ‒ derived data, we demonstrate the water circulation, temperature, salinity, and chemical parameter distributions in the western Chukchi Sea in the summer 2002 and summer 2019. In summer of 2002, the subsurface layer in the western Chukchi Sea was composed of Bering deep basin water with the salinity of about 33.0. In 2019, the deep layer of the western Chukchi Sea was occupied by winter Bering Sea shelf water with the salinity of 32.2–32.5. An inflow of Arctic water (increased salinity/density and low concentration of nutrients) through the Herald Canyon led to cyclonic gyre water circulation in the southwestern Chukchi Sea. The cyclonic gyre in the southwestern Chukchi Sea was characterized by anomalously low pCO2 in the surface and subsurface layers, low pH and high pCO2 in the bottom water, and high biomass of benthos.